This invention relates to spray painting systems, and more particularly to a spray painting optimization system that can reduce paint waste and improve operator efficiency in application of paint or other coating to a surface.
Spray paint guns spray paint from a nozzle with compressed air onto a surface being painted. In order to optimize the quality of the finish of the painted surface, it is important to maintain the spray gun at an optimal position relative to the surface. Most importantly, the distance of the nozzle from the surface and the angle of the spray gun relative to the surface must be carefully controlled in order to apply the paint to the surface in a manner which minimizes paint waste and maximizes efficiency in applying the paint to the surface while maintaining the appropriate thickness of paint applied.
Co-pending application Ser. No. 08/504,370 filed Jul. 19, 1995 (now U.S. Pat. No. 5,598,972 issued Feb. 9, 1997, assigned to the same assignee as the present application, discloses an optical spray paint optimization system in which a laser device is mounted alongside a spray gun. The laser device emits a split beam which converges toward the surface. The operator positions the spray gun such that the light beams converge into a single point of light on the surface, for providing a visual indication as to whether the nozzle is a predetermined distance from the surface. The point of convergence of the light beams can be adjusted to provide the optimal distance of the nozzle from the surface to accommodate for varying operator conditions and paint characteristics.
Co-pending application Ser. No. 08/658,935 filed May 30, 1996, also owned by the same assignee as the present application, discloses an optical feedback system utilizing a laser device mounted alongside a spray gun in which light from the laser is reflected from the surface and received by one or more optical sensors or input devices interconnected with a processor. The optical input devices provide input signals to the processor which are used to provide a real-time indication to the operator as to the position of the nozzle, so as to enable the operator to place the nozzle and apply the paint in a manner which minimizes waste and maximizes efficiency in applying the paint to the surface. The optical input devices can also supply raw data to a processor or computer after the painting operation, to analyze overall efficiency and compliance with standards or other operating parameters.
The disclosures of the above-referenced applications are hereby incorporated by reference.
As set forth above, a light beam, such as a beam emitted by a laser, can be effectively used in combination with a paint spray system in order to optimize application of the paint to the surface. Past efforts have involved mounting a laser device to the spray gun in somewhat of a retrofit manner, typically at a location adjacent the nozzle portion of the spray gun. This mounting of the laser device moves the overall center of gravity of the assembly when compared to that of a spray gun without a laser device, and to which an operator is accustomed. The operator must compensate by adjusting his grip on the gun and the motions used to move the gun when applying the paint to the surface.
It is an object of the present invention to incorporate a light-emitting device, such as a laser device, into a spray gun without any significant effect on the overall center of gravity of the spray gun. It is a further object of the invention to incorporate a laser-type light emitting device into the housing of the spray gun without significantly altering the overall configuration of the spray gun. Still another object of the invention is to incorporate a laser-type light emitting device into a spray gun and to emit a pair of convergent light beams from the spray gun toward the surface to provide a reference in positioning the spray gun relative to the surface.
In accordance with the invention, a hand-held spray gun for applying a coating to a surface includes a housing having a handle and defining an interior. A nozzle is mounted to the housing for discharging the liquid coating from the spray gun. A light generating device is disposed within the interior of the housing and includes a light-emitting source for communicating a light beam from the light generating device exteriorly of the housing. The housing defines a forward end and a rearward end. The handle is located toward the rearward end of the housing, and the nozzle is located toward the forward end of the housing. The light generating device is preferably located toward the rearward end of the housing, and the light-emitting source is preferably located toward the forward end of the housing. The light generating device preferably includes a pair of light-emitting sources for emitting a pair of light beams toward the surface. A first one of the light-emitting sources is preferably located toward the forward end of the housing, and a second one of the light-emitting sources is preferably located rearwardly of the first light-emitting source. In a preferred form, the first light-emitting source is located so as to emit a light beam from a location immediately adjacent the nozzle. The pair of light-emitting sources are arranged so as to emit a pair of light beams which converge in a direction toward the surface from the spray gun, to enable a user to ascertain the position of the spray gun relative to the surface by observing the distance between the two light beams. An adjustment mechanism is associated with one of the light-emitting sources for adjusting the angle at which the light beams converge, to enable a user to calibrate the distance of the spray gun from the surface when the light beams are coincident on the surface. The invention further contemplates a shut-off mechanism for selectively preventing emission of one of the light beams, such that the other light-emitting source emits a single light beam toward the surface from the light generating device. This enables a user to provide a reference on the surface when it is desired to spot-apply the coating on the surface. In one embodiment, the shut-off mechanism is in the form of a closable door member mounted to the housing and movable between an open position in which the second light-emitting source emits a light beam from the housing, and a closed position in which the door prevents the light beam from the second light-emitting source from being discharged from the housing. One of the light-emitting sources is located immediately adjacent the nozzle, and the shut-off mechanism is associated with the other of the light-emitting sources such that the single light beam emitting from the spray gun emanates from a location adjacent the nozzle.
The invention also contemplates an improvement in a spray gun including a housing, substantially as set forth in the foregoing paragraph.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.